If he includes cured meats, there are more options.
Sommerfest has the brat and frank, just discard the bun.
Katsura - edamame side
Kringla - Norwegian chef salad, picking out the potatoes, fruit cup
La Cantina - salads with beef or chicken, guacamole side, are refried beans okay?
Les Halles - Nicoise salad, picking out the potatoes, omitting dressing and see if they can do an olive oil drizzle
Not QS but Tutto Gusto has a couple of Gusto plates that will work, if someone will share and eat the items he doesn't.
Choza has some yummy sounding guacamole and the tacos al pastor can be deconstructed. Tostada pollo served without cheese, discarding the tostada.
Of course, Sunshine Seasons has several more items but it's not in WS.